<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      :root {
        --color: #fc6627;
      }
      h1 {
        background-color: var(--color);
      }
      button {
        color: #fff;
        padding: 10px 20px;
        background-color: var(--color);
        border-radius: 5px;
        border: none;
      }
    </style>
  </head>
  <body>
    <h1>标题</h1>
    <button>按钮</button>
  </body>
</html>
